Bismuth compounds are used in cosmetics and in medical procedures. As the toxicity of lead has become more apparent in recent years, alloy uses for bismuth metal as a replacement for lead have become an increasing part of bismuth's commercial importance.

While bismuth was traditionally regarded as the element with the heaviest stable isotope, it had long been thought to be unstable on theoretical grounds. Not until 2003 was this demonstrated when researchers at the Institut d'Astrophysique Spatiale in Orsay, France, measured the alpha emissionhalf-life of 209Bi to be 1.9 x 1019 years,[2] meaning that bismuth is very slightly radioactive, with a half-life over a billion times longer than the current estimated age of the universe. Due to its extraordinarily long half-life, for nearly all applications bismuth can be treated as if it is stable and non-radioactive. However, the radioactivity is of academic interest because bismuth is one of few elements whose radioactivity was suspected, and indeed theoretically predicted, before being detected in the laboratory.

Though virtually unseen in nature, high-purity bismuth can form distinctive hopper crystals. These colorful laboratory creations are typically sold to collectors. Bismuth is relatively nontoxic and has a low melting point just above 273°C, so crystals may be grown using a household stove. This carries significant risk of burns and should not generally be attempted without extensive metal-smelting experience, and the resulting crystals will tend to be disappointing when compared to lab-grown crystals.

Artificial bismuth was commonly used in place of the actual mineral. It was made by hammering tin into thin plates, and cementing them by a mixture of white tartar, saltpeter, and arsenic, stratified in a crucible over an open fire.[3]

Bismuth was also known to the Incas and used (along with the usual copper and tin) in a special bronze alloy for knives, [2]

In the Earth's crust, bismuth is about twice as abundant as gold. It is not usually economical to mine it as a primary product. Rather, it is usually produced as a byproduct of the processing of other metal ores, especially lead, but also tungsten or other metal alloys.

The average price for bismuth in 2000 was US$ 7.70 per kilogram. It is relatively cheap, since like lead (but to a much lesser extent), it is radiogenic, being formed from the natural decay of uranium and thorium (specifically, by way of neptunium-237 or uranium-233).

In 1997 an antibody conjugate with Bi-213, which has a 45 minute half-life, and decays with the emission of an alpha-particle, was used to treat patients with leukemia.

In 2001, Professor Barry Allen and Dr. Graeme Melville at St. George Hospital in Sydney successfully produced Bi-213 in linac experiments which involved bombarding radium with bremsstrahlung photons. This cancer research team used Bi-213 in its Targeted Alpha Therapy (TAT) program.

In the early 1990s, research began to evaluate bismuth as a nontoxic replacement for lead in various applications:

As noted above, bismuth has been used in solders; its low toxicity will be especially important for solders to be used in food processing equipment and copper water pipes.

Replacement for lead in shot and bullets. The UK, U.S., and many other countries now prohibit the use of lead shot for the hunting of wetland birds, as many birds are prone to lead poisoning due to mistaken ingestion of lead (instead of small stones and grit) to aid digestion. Bismuth-tin alloy shot is one alternative that provides similar ballistic performance to lead. (Another less expensive but also poorer-performing alternative is "steel" shot, which is actually soft iron.)

Bismuth core bullets are also starting to appear for use in indoor shooting ranges, where fine particles of lead from bullets impacting the backstop can be a chronic toxic inhalant problem. Due to bismuth's crystalline nature, the bismuth bullets shatter into a non-toxic powder on impact, making recovery and recycling easy.[citation needed] The lack of malleability does, however, make bismuth unsuitable for use in expanding hunting bullets.